Amelia Womack, the deputy leader of the Greens, described the policy as "bold" and argued that it sets her anti-austerity party apart from the pack.

"In the midst of such struggle in this country, the Green Party are offering something unique: hope. We make this one very clear promise to voters: we will always stand for an economy, a society, that works for the many, not just the few," she said.

The left-of-centre party have also pledged to keep Independent Living Fund, which provides money to help disabled people live an independent life. The policy would cost around £300m.

But the SNP did not take the allegations of racism lightly and subsequently hit back at Farage's "disgraceful" remarks.

"These disgraceful comments – which aren't just offensive to the SNP, but to the majority of people in Scotland on current polls – show exactly why the people of Scotland reject Ukip," said Humza Yousaf, an MSP for the SNP.